WIKA 54_twintemp - Manual (Page 12)

GB
14004105.01 05/2011 GB/D/F/E
12 WIKA operating instructions model 54, Twin-Temp
■ Residual media in dismounted instruments can result
in a risk to persons, the environment and equipment.
Take sufficient precautionary measures.
For information on returning the instrument see chapter
9.2 "Returns".
8. Faults
Faults Causes Measures
No signal/ line
breakage
Mechanical load too high
or overtemperature
Replace probe or measuring
insert with a suitable design
Erroneous measured
values
Sensor drift caused by
overtemperature
Replace probe or measuring
insert with a suitable design
Sensor drift caused by
chemical attack
Use a design with
thermowell
Erroneous measured
values (too low)
Entry of moisture into
cable or measuring insert
Replace probe or measuring
insert with a suitable design
Erroneous measured
values and response
times too long
Wrong mounting geome-
try, for example mounting
depth too deep or heat
dissipation too high
Temperature-sensitive area
of the sensor must be inside
the medium, and surfaces
must be isolated
Deposits on the sensor or
thermowell
Remove deposits
Measurement signal
"comes and goes"
Cable break in connecting
cable or loose contact
caused by mechanical
overload
Replace probe
Corrosion Composition of the medium
not as expected or modified
or wrong thermowell
material selected
Analyse medium and then
select a more-suitable
material or replace
thermowell regularly
7. Maintenance and cleaning / 8. Faults